In general, various measures are tried to prevent a water meter from being frozen and burst in winter.
For example, in the case of a water meter exposed to the outside, it is wrapped with a heat insulating material such as Styrofoam or the like to prevent the water meter from being frozen. In the case of a water meter accommodated in a protection box, it is covered with a heat insulating material. Then, the protection box is filled with rice husks, old clothes, sawdust or the like, thereby thermally insulating the water meter from an ambient air and preventing the water meter from being frozen.
However, such a method cannot be a positive choice for preventing a water meter from being frozen. Even if the water meter is thermally insulated in this manner, when the temperature drops significantly, the water meter may be frozen and burst.
On the other hand, as another method for preventing a water meter from being frozen, a faucet valve in a house may be opened so that tap water in a water pipe can continuously flow without being stagnant, thereby preventing a water meter from being frozen.
However, in such a method, if the faucet valve is excessively opened due to erroneous adjustment of a valve opening amount, a large amount of water may be wasted. If the opening degree of the faucet valve is too small, the water meter may be frozen.
A user who exists indoors is difficult to accurately know the external temperature and may open a faucet even at a temperature at which a water meter is not frozen. Thus, water may be excessively wasted. If water continues to flow through a faucet, a user may unconsciously close a faucet valve, as a result of which a water meter may be frozen.